algae and KH

[DougSupreme]

Does algae deplete alk? I can get my alk up to a reasonable 8DKH but by the next day it has dropped to around 4DKH. The only thing that I can figure is the algae is somehow depleting the alk. Possible, or just an illusion?

BTW, if anyone needs any hair algae, feel free to PM me and I'll send you some :)

[Randy Holmes-Farley]

Only calcerous algae, such as halimeda or coralline algae consume alkalinity. Green hair algae, cyanobacteria,and diatoms do not deplete alkalinity.

What else is in the aquarium?

[DougSupreme]

There is one small montipora, a medium sized frogspawn, some xenia, and a mushroom. I do have a little neomeris algae growing on my rocks. It's just very difficult to maintain my alk. My calcium was elevated to around 500+ by the addition of Ball pickling lime, but it never seemed to affect my alk. maybe I just need to add buffer until my Cal drops to around 380-400 then I can expect my alk to level out around say 8dkh (2.8meq/l)

[DougSupreme]

as of 5 minutes ago, my Calcium is at 480 and my alk is at 6.4 DKH

[Randy Holmes-Farley]

The pickling lime is adding a balanced amount of alkalinity to the calcium it adds. You may simply not be adding enough to meet the calcium and alkalinity demand of the aquarium.

The calcium is probably high for other reasons. Are you using Oceanic salt?

Yes, adding buffer, along with, or instead of the limewater, until the calcium drops to 450 ppm or so is a fine plan. :)


These articles may help:

Solving Calcium and Alkalinity Problems
http://www.advancedaquarist.com/issues/nov2002/chem.htm

When Do Calcium and Alkalinity Demand Not Exactly Balance?
http://reefkeeping.com/issues/2004-12/rhf/index.htm